Do you use dashes in your URLs?
For maximum readability and SEO use kebab-case (dashes) in your URLs.
Learn more on Best Practices for URL Structure.
Figure: Bad example - No kebab-case in URL
Figure: Bad example - PascalCase (better readability and still works in small caps, but other people might share it without the MixedCase)
northwind.com/page on word documentation
Figure: Bad example - spaces it will show up in your URL structure as 20%, which is bad for readability and SEO
Figure: OK example - underscored (snake_case) URLs have good readability but are not recommended by Google
Figure: Good example - kebab-case is recommended by Google. Note: Don't use any uppercase
Not for domains! This is only for pages and documents. Domains are bad when they have dashes in them.
Read more on SEO 101: Hyphens vs. Underscores in URLs.
You can install the IIS URL Rewrite Module for IIS7 you can make ugly URL's much more friendly.
The caveat here is that it will only work if the URL is in the clear on the page.
Note: This could only be done with certain links as others are postbacks as well.